We've got two numbers: 1252 and 2404. Let's find their sum.

Step 1: We'll start by adding the digits 2 & 4 in column 1 and get 6.

Step 2: We'll start by adding the digits 5 & 0 in column 2 and get 5.

Step 3: We'll start by adding the digits 2 & 4 in column 3 and get 6.

Step 4: We'll start by adding the digits 1 & 2 in column 4 and get 3.

So, 1252 + 2404 = 3656.

